New55, a company who’s primary goal is to bring back Polaroid’s Type 55 instant film, has released a new product that is making quite a splash. It’s called R3 monobath developer. Usually developing black and white film or paper is a three step process followed washing any remaining chemical residues off the film. You develop, stop, and fix. Developing brings out the latent image on the film or paper, stop stops the development and neutralizes or rinses any developer off the emulsion, and fix makes the emulsion no longer sensitive to light so what’s left is permanent. A monobath is just like it sounds, one bath, no three steps, just the one and you are ready to wash. How is this possible? It must be some org of chemistry wizardry right? Nah. It’s surprisingly simple.
See film needs the develop and fix steps and it need them in that order. Fix first and you’ll get nothing from developing, a black roll or sheet. Stop keeps the developer from contaminating the fix. Technically you don’t need it but if too much developer builds up in the fix you’ll start developing again before fixing is over which changes the density of your negatives. In short skipping stop in a traditional processing paradigm reduces consistency. Developer will also increase fixing time and exhaust it faster. Fix contaminated developer is less common but also bad as any granules that are fixed before development don’t get developed.
So how does a mono bath work? Essentially it’s a fast developer and a pokey fixer in one solution. The developer works faster than the fix and when the fix kicks in development is near completion. Monobaths chemically time development. Polaroid instant film was probably the biggest commercial usage of monobaths. The have a “pod” that contains a chemical liquidy-goo which coats the emulsion when the pod is broken. That one goo has to do all the work. Polaroid Type 55 produced both a black and white positive and a negative of the image taken. It was generally regarded as a super awesome film and loads of photographers loved it including Ansel Adams. When trying to recreate this wonder of the film world the first thing you’re going to need is a black and white monobath to put in the pod to process the film and direct positive paper (which Ilford just announced it will be producing again!).
Enough of the back story, what is this R3 monobath stuff? Well if you look at the R3 MSD (Materials Safety Data) sheet it pretty clearly states that it’s Kodak HC110 developer, Ammonium, and Rapid Fix. Wait, Rapid Fix? I thought you need a pokey fix. Yup you do, it needs to be slower than the developer. Developer is also very temperature sensitive whereas fix much less so. New55 recommends warming the R3 up to 80degF which is pretty warm for a developer. At this temp, the development time for new Tmax is around 2 minutes with the most highly concentrated HC110 working solution. The fix time for rapid fix is 2-5 minutes. The recommended time for the R3 is 6 minutes probably because the fix is contaminated with developer and buffered with ammonium.
This is actually a very similar formula to one that popped up on a 2004 news group rec. photo.darkroom by Donald Qualls:
My specific HC-110 monobath was developed after taking a statement in
Anchell & Troop as a challenge; they said they weren’t aware of anyone
developing a monobath that used rapid fixer instead of hypo, because
development would have to be exceedingly rapid. Well, let’s see –
HC-110 Dilution A at 75 F is pretty darned fast; how much do I need to
dilute the fixer to get the fixing time to six minutes? That much?
Does it still have enough capacity for 135-36? Cool!
I had to adjust the alkalinity and fixer proportion after the first
test, but the second was a complete success.
For 256 ml of HC-110 Dilution A, instead of pure water, use:
50 ml household clear ammonia
10 ml Ilford Rapid Fixer concentrate
Water to make up 256 ml including the HC-110 concentrate for Dilution A
At 75F, this mix develops and fixes 400TX in well under ten minutes,
likely as little as six (I haven’t opened the tank that early, but
development should be completed in under three minutes and I lose some
shadows to fixing away the halide before the shadows develop; it might
work in four minutes total time).
It’s probably no surprise that I’m not a big proponent of monobaths and that’s the fairly default perspective from the photographic community. I looked in six different darkroom books including The Darkroom Cookbook (which a pretty definitive guide on mixing darkroom chemicals) and Ansel Adams’ The Negative and none of them even mention monobaths. I believe that you are necessarily losing something by fixing and developing at the same time. I’ve read that monobaths were marketed to photojournalists back in the day but it didn’t catch on. Probably because the mixture is chemically timed and if you’re not using a film that lines up with that timing you’re out of luck. Even the HC110 page mentioned above states that development times under 5 minutes are difficult to control. Judging from the development times I’d guess that R3 would make a mess out of fast films. According to the R3 resource page you have to pull iso 3200 films to 800 (two stops) for R3 to work properly with them. It states that base fogging is normal with monobath developers. The resource page also eschews the idea that monobaths need to be tailored to a film by stating the person that claimed that was a Kodak crony. They then go on to answer the “if it’s so great how come no one uses it?” question by citing instant film. Instant films had monobaths tailored for them! They were packaged together. The answer to “is it archival” is pretty much a side step.
I like the New55 project. I want very much to use New55 film someday. I was pleasantly surprised when their kickstarter got funded. What kind of tweaks me about R3 is that monobaths are an experimental process. R3 is not being marketed as an experimental developer. If photographers could skip two steps (stop and fix) and still get results that were “good enough” they would. R3 might fit some niches very well, some photographers may like or love it, but I have a hard time believing you wouldn’t get better results with regular HC110 at a more normal developing temperature followed by stop and fix. What’s more it’s superficially being marketed as a New55 developed product and it is not. While the correct attributions aren’t exactly hidden, they are kind of buried. Most of what I’ve read online and on social media is excitement over a commercial monobath and a “new” developer. It’s largely hype with very little grounding. If you ever get your hands on some New55 you’ll probably be using some R3 (probably with some thickening agents so it’s not so watery) and that’s great. That’s how it’s supposed to be, but it’s not a necessity in the darkroom. They’re just trying to make some extra cheddar off of some R&D that is needed to make New55 a reality and I guess I can’t really blame them for that.